1. Field of the Invention
This invention relates generally to a circular insert tool holder assembly which holds a resharpenable insert tool and can be mounted in a standard circular tool post. More particularly, the assembly relates to a circular insert tool holder and an adjustable wedge member for holding the insert tool in the tool holder and for bringing a cutting edge of a new or resharpened insert tool up to "center" without rotational adjustment of the tool holder assembly.
2. Background Art
Various machine tools such as Brown & Sharpe screw machines, Index automatic bar machines and multiple spindle machines are equipped to receive a standard circular tool post. A circular form tool or a circular insert tool holder can be mounted in the tool post.
Standard circular form tools are rotatably mounted within the circular tool post. The circular form tool has a cutting edge on the circular form tool itself. As the cutting edge is sharpened, the circular form tool must be rotated within the circular tool post to keep the cutting edge up to "center". Continuous adjustment of the circular form tool causes significant down time of the machine.
Circular insert tool holders are designed to receive resharpenable insert tools which have a cutting edge for cutting a work piece. The known holders cannot keep a resharpened insert up to "center" after the insert tool has been resharpened because the insert tool is clamped down onto the holder such that after the insert tool has been sharpened and replaced, the new cutting edge is positioned below its original position.
Rotation of the circular insert tool holder to adjust the cutting edge of a resharpened insert tool back up to its original position will change the angle at which the insert tool meets the workpiece and is unacceptable. Accordingly, the resharpened insert tools cannot be adjusted to keep the cutting edge up to "center" without changing the orientation of the insert tool such that the required "rake angle" or "clearance angle" are changed.
It is desirable to provide a circular insert tool holder assembly in which an insert tool can be removed and replaced by either a new or resharpened insert tool and can be repositioned up to "center" without rotational adjustment to the circular insert tool holder and still position the insert tool having the required "rake angle" and "clearance angle".